408 LT1 build
03-29-2008, 11:09 PM
#62
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Join Date: May 2006
Location: Ohio
Posts: 1,855
Just wanted to let everyone know the 408 is alive! I've had it running a few times and had it up to temp a couple of times with no leaks so far. (pray for me please... lol)
It has been a interesting ordeal to say the least. Thanks for everyone's input on the subject and I will try to give updates as to weather it fails or not.
It has been a interesting ordeal to say the least. Thanks for everyone's input on the subject and I will try to give updates as to weather it fails or not.
408 lt1 sounds mean haha.
03-30-2008, 12:00 PM
#66
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Thread Starter
Join Date: Jan 2008
Posts: 66
I have heard hard block cracks easily and will leak, but I honestly don't know. I used devcon to fill and fluid weld on the hole.
My cam is 270 280 at .050 .711 .691 lift on a 110 +4. piston to valve is at minimum on intake has plenty on ex. Heads are trick flows with miild port job.
As for building a stoudt 400 with efi, sure why not if that's what you want. I wanted to keep it an lt1. We have one advantage as LT1 owners and that is reverse flow cooling, higher compression without racegas why not utilize it?
So many options so little money, you gotta pick one!
I'm working on the pics.
My cam is 270 280 at .050 .711 .691 lift on a 110 +4. piston to valve is at minimum on intake has plenty on ex. Heads are trick flows with miild port job.
As for building a stoudt 400 with efi, sure why not if that's what you want. I wanted to keep it an lt1. We have one advantage as LT1 owners and that is reverse flow cooling, higher compression without racegas why not utilize it?
So many options so little money, you gotta pick one!
I'm working on the pics.
03-30-2008, 12:20 PM
#67
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Join Date: Dec 2005
Location: Knoxville, TN
Posts: 197
The man wants to build a 408. Let him build a 408! Geez. Why not do this why not do that...... yadda yadda yadda. Because its a 408 LT1 build project thats why. I think its an interesting project and cant wait to see it done.
03-30-2008, 01:46 PM
#68
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Join Date: Aug 2007
Location: walnutport, PA
Posts: 156
i not going against him, but was thinking for less money, and more reliability, he could have done a 40 over 400.
but he has a good point about reverse cooling.
hey im still with you on building a 408 from a 350, and more power to you. my response was just another thought.
aaron
but he has a good point about reverse cooling.
hey im still with you on building a 408 from a 350, and more power to you. my response was just another thought.
aaron
03-31-2008, 02:48 AM
#69
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Join Date: Oct 2000
Location: Kilgore TX 75662
Posts: 3,372
Congrats man! Glad to hear of no leaks
I thought of this thread recently because David Vizard recently did an article about building a 408 out of a 350 block to make 600hp NA on pump gas. I think it was in Popular Hot Rodding? I didn't like it because there were very few details mentioned. They didn't mention rod length, piston compresison height, compression ratio or any real details. It was basically a big advertisement for T&L Engines or whatever they are called.
I thought of this thread recently because David Vizard recently did an article about building a 408 out of a 350 block to make 600hp NA on pump gas. I think it was in Popular Hot Rodding? I didn't like it because there were very few details mentioned. They didn't mention rod length, piston compresison height, compression ratio or any real details. It was basically a big advertisement for T&L Engines or whatever they are called.
03-31-2008, 10:20 AM
#70
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Join Date: Nov 1998
Location: St Charles MO, USA
Posts: 575
thing sounds mean as hell, i'll get a video of it when i go back over for some more tuning.
04-02-2008, 01:11 PM
#72
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Location: Robinson Township, PA
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500 hp at 6,700 rpm would be more realistic and affordable....
04-02-2008, 01:19 PM
#73
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Join Date: Feb 2008
Location: Robinson Township, PA
Posts: 292
30 lb/hr injectors are good to at least 505 hp at 85% duty cycle. If the 408 will be turning 6,200 rpm ± 100 rpm, then it'll be making about 489-505 hp normally aspirated.
04-02-2008, 01:33 PM
#74
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Join Date: Feb 2008
Location: Robinson Township, PA
Posts: 292
A 408 rotating at 6000 rpm should have 30 more hp than a 383 due to the additional air flow. Or to put it another way, the 408 can produce the same hp as a 383 but at a lower rpm. For example, a 408 could make 500 hp at 6,200 rpm. A 383 would need to rotate to 6,700 rpm for the same power. [Estimated numbers]
04-02-2008, 01:43 PM
#75
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Join Date: Jan 2002
Location: Mobile, Ala..USA
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I see you like math, my 383 makes 600(ish) hp on pumpgas at 6500 rpm, so the other 2700rpm is only worth 50 hp??
I have seen a 396 LT1 make 740 hp naturally aspirated and not turn past 7500 rpm. How do you explain that?
David
Last edited by FASTFATBOY; 04-02-2008 at 01:57 PM.